<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <style>
    button.active {
      background-color: red;
    }

    .content {
      width: 200px;
      height: 200px;
      border: 1px solid #333;
    }
  </style>
</head>

<body>
  <div id="app">
    <button 
      v-for="(el,index) in tabs" 
      @click="tabChange(index)" 
      :class="{active: num === index}">
      {{el.title}}
    </button>
    <div 
      v-show="num === index" 
      v-for="(el,index) in tabs"
      class="content">
      {{ el.content }}
    </div>
    
  </div>
  <script src="./vue.js"></script>
  <script>
    const vm = new Vue({
      el: '#app',
      data: {
        num: 0,
        tabs: [
          {
            title: '标题1',
            content: '内容1'
          },
          {
            title: '标题2',
            content: '内容2'
          },
          {
            title: '标题3',
            content: '内容3'
          }
        ]
      },
      methods: {
        tabChange(index) {
          this.num = index;
        }
      }
    })
  </script>
</body>

</html>